Finding a plugin

In this recipe, we'll follow a procedure to find a plugin appropriate to a specific monitoring task. We'll start by checking whether an existing plugin is already available to do just what we need. If we can't find one, we'll check whether we can use another more generic plugin to solve the problem. If we still find that nothing suits, we'll visit Nagios Exchange and search for an appropriate plugin.

Getting ready

You should have a Nagios Core 4.0 or newer server running with a few hosts and services that are configured already, and you'll need to have a particular service on one of these hosts, which you're not yet sure you need to monitor.

We'll use a simple problem as an example; we have a server named troy.example.net that runs an rsync(1) process that listens on port 873. We're already monitoring the host's network connectivity via PING, but we'd like to have Nagios Core check whether the rsync(1) server is available and listening at all times, in case it crashes while...